Electric track switch



Oct. 25, 1932. c, SEATQN 1,884,884

ELECTRIC TRACK SWITCH Filed Oct. 2, 1950 #557542 0. 56A ro/v Patented Oct. 25, 1932 PATENT OFFICE CHESTER O. SEATON, OF LOUISVILLE, KENTUCKY ELECTRIC TRACK SWITCH Application filed October 2, 1930. Serial No. 486,020.

The object of my invention is to provide protecting means for certain parts of the ground magnet of a track switching mechanism which has found wide use for operating track switch points in the tracks of electric railway systems. Track boxes are usually provided for housing the apparatus which includes a water tight cylinder constructed with a pair of solenoids, occasionally only one, for operating the switch point to one of two positions according to the solenoid energized, selected by the approaching car.

Inasmuch as these cylinders containing the solenoids are placed below the street or right of way surfaces in boxes, a ready means for collecting water with the usual suspended foreign matter such as dirt, sand, et cetera, is formed. It has become quite a problem for protecting not only the solenoids, but the reciprocating plunger which operates in the tube, under heavy pressures. It has been the usual practice to build these parts of relatively heavy materials and to permit the abrasion to go on for as long as the elements last,

then renew same which means not only expense but an interruption of operations which is quite a factor especially in street railway service which must be performed amid the existing conditions, usually in trafiic and frequently inclement weather.

The main object of my invention is to pro vide an inexpensive and very efficient means of protecting the wearing parts and to provide very much longer life and reduce the total ultimate cost for services rendered.

The accompanying drawings are used to more fully explain the improvements of a type of apparatus to which the invention is directly applicable.

Figure 1 is a plan view of a section of a rail and switch point, and adjacent is the conventional ground box for an electric switch point throwing mechanism with the lid removed and not shown. Fig. 2 is a vertical cross sectional view of the electromagnetic cylinder and plunger, coils et cetera. Fig. 3 is a cross section of the rear or left hand end of the cylinder and is taken along the line AA. Fig. 4 is an enlarged cross sectional view of a section of the plunger, section of the front or right hand end of the cylinder together with the central tube and its appurtenances.

In Figure 1, a heavy ground box is shown without the lid which may be of any conventional form. In this box is lodged a cylinder 11, secured in place by clamp 12 and bolts 13, containing solenoids 21 and 22. Projecting from the cylinder is a plunger which is constructed with a magnetic member 14 and a non-magnetic member 15 which is fashioned with a head 16 so as to receive a leg of the U-shaped link 17 while the other leg is articulated with a conventional toggle mechanism for holding the mechanism in a given position after the solenoid and plunger have op erated. The ground magnet 11 is closed at both ends. End 18 is fashioned with external threads 18A for effecting a tight joint through gasket 19 with the housing, and it is also provided with internal threads 18D for receiving the central non-magnetic tube 20 with radial ducts 1813 which connect with the interior of the non-magnetic tube and the atmosphere through threaded apertures 18C.

The solenoids 21, 22 can be placed on to central tube 20 in any conventional way. However, in the selected structure the bobbin type is employed and located on the center tube by spacers 23, 24 and heavy spring 25 for elastically securing them in a selected place.

Tube 20 extends through head 10A and is externally threaded to receive bearing nut 26 which is arranged to secure gasket 27 against head 10A and thereby prevent any ingress of elements. This nut carries external threads to receive gland 27A and is made with a substantial bearing face 26A preferably of lesser diameter than the central tube for the pur pose for supporting the plunger throughout its operations and to prevent it from abrading the interior of the central tube at a place that is weakened by reason of the threads under the nut which is normally formed without this bearing but used solely for securing the several parts together. Gland 27A is provided with a bearing surface 27 B of substantially the same diameter 26A to support and guide the plunger and thereby form an auxiliary bearing. The apparatus can be made with both bearings as illustrated or either one can be omitted without departing from the spirit of the invention. This gland 27A confines a suitable gasket 28 of any con ventional design for the purpose of preventing the ingress of foreign material and also confine a lubricant lodged in the central tube. 26B is a washer to prevent distortion of the soft gasket 28 and can be employed to supplement bearing surfaces 26A, 27 B, or it could be so constructed as to function as a unitary bearing for the plunger. After the grounc magnet parts are assembled and ready for installation in the ground box one of the ducts 1813 will be at the top, or nearly so, and is sulliciently large to permit breathing incident to the plungers operation while the remaining ducts are closed off in any suitable manner, as by theinsertion of screw 29 in each of the threaded apertures 18C. A plurality of these ducts are necessary as it is practically impossible to predetermine the position of a single duct were only one provided the thickness of the gasket and the formation of the threads as well as other factors all contribute to a random setting when head 18 is finally screwed into housing 11.

I do not wish to limit myself other than by the appended claims:

1. In an electro-magnet, comprising a mag netic plunger, a magnetic shell included in the magnetic path of the flux'of said magnet, a center non-magnetic tube mounted therein and sealed to theends of said shell with closures, windings associated with said tube which is provided with an open end through which passes the connection from the plunger to the device to be operated, said tube being provided with an auxiliary plunger bearing, said tube extending beyond the casing of one of the closures.

2. In an electro-magnet,comprising a magnetic plunger, a magnetic shell included in the magnetic path of the flux of said magnet, a center non-magnetic tube mounted therein and sealed to the ends of said shell with closures, windings associated with said tube which is provided with an open end through which passes the connection from the plunger to the device to be operated, said tube extending beyond the casing of one of the closures and equipped with means for effecting an hermetical seal.

3. In an electro-magnet, comprising a magnetic plunger, a magnetic cylinder shell included in the magnetic path of the flux of said magnet, a center non-magnetic tube mounted therein and sealed in the ends of said shell with closures, windings associated with said tube which is provided with an open end through which passes the connection from the plunger to the device to be operated, said tube being provided with an auxiliary plunger bearing, said tube extending beyond the wall with said tube which is provided with an open end through which passes the connection from the plunger to the device to be operated, one of said closures being provided with a plurality of radial ducts which connect with the interior of said tube and the atmosphere and further provided with means for sealing one or more of said ducts.

5. In an electroanagnet, comprising a magnetic plunger, a magnetic cylinder shell, included in the magnetic path of the flux of said magnet, a center non-magnetic tube mounted therein and sealed in the ends of said shell with closures, windings associated with said tube which is provided with an open end provided with an auxiliary renewable plunger bearing through which passes the connection from the plunger to the device to be operated, one of said closures being provided with a plurality of radial ducts which connect with the interior of said tube and the atmosphere and further provided with means for sealing one or more of said ducts.

6. In an electro-magnet, comprising a magnetic plunger, a magnetic cylinder shell,

included in the magnetic path of the flux of said magnet, a center non-magnetic tube mounted therein and sealed in the ends of said shell with closures, windings associated with said tube which is provided with an open end provided with an auxiliary renewable plunger bearing and a seal through which passes the connection from the plunger to the device to be operated, one of said closures being provided with a plurality of radial ducts which connect with the interior of said tube and'the atmosphere and further provided with means for sealing one or more of said ducts.

7. In an electro-magnet, comprising a magnetic plunger, a magnetic cylinder shell included in the magnetic path of the fiux of said magnet, a center non-magnetic tube mounted therein and sealed in the ends of said shell with closures, windings associated with said tube which is provided with an open end through which passes the connectien from the plunger to the device to be 0perated, said tube being provided with an auxiliary plunger bearing, said tube extending beyond the wall of one of the closures and being provided with an external thread which engages the internal thread of a nut having an internal bearing surface, said nut being further provided with an external thread which engages with an internal thread of a gland which is also provided with an internal bearing.

8. In an electro-magnet, comprising a magnetic plunger, a magnetic cylinder shell included in the magnetic path of the flux of said magnet a center non-magnetic tube mounted therein and sealed in the ends of said shell with closures, windings associated with said tube which is provided with an open end through which passes the connection from the plunger to the device to be operated, said tube being provided with an auxiliary plunger bearing, said tube extending beyond the wall of one of the closures and being provided with an external thread which engages an internal thread of a nut having an internal bearing surface, said nut being further provided with an external thread which engages with an internal thread of a gland which is also provided with an internal bearing, said gland and nut being so correlated as to confine a sealing member between parallel related faces.

9. In an electro-magnet, comprising a magnetic plunger, a magnetic shell included in the magnetic path of the flux of said magnet, a center non-magnetic tube mounted therein and sealed to the ends of said shell with closures, windings associated with said tube which is provided with an open end through which passes the connection from the plunger to the device to be operated, said tube being equipped with an auxiliary plunger bearing of less inside diameter than said tube, said tube extending beyond the casing of one of the closures.

In testimony whereof I aflix my signature.

CHESTER O. SEATON. 

